Our bodies are intended to function as "well-oiled machines,"
which receive input from the senses, and organize and process that information to be able to use it appropriately, or to act
on it. Our senses include hearing, seeing, touching, tasting, and feeling, as well as the processes of movement and gravity.
When these systems are all working properly, and the brain is able to correctly interpret the information they send, we refer
to this process as sensory integration; the senses are working together! However, when there are imperfections in this system,
we call that "sensory integration dysfunction" (SID or DSI Dysfunction
of sensory integation) Although there are many variations in the ways that sensory integration dysfunction (or sensory processing difficulties) can present itself, there are two main
underlying problems. The first is when a person receives too much sensory input; in effect, their brain is overloaded. The
second is when a person does not receive enough sensory input, resulting in a "craving" of sensory information. The following
section will discuss how each of the senses affects behaviors, as well as potential problems which arise when sensory
integration dysfunction is present.
Hearing. We use our ears to hear voices, music, alarms and sirens, as well as "noise" around us generated by electronic equipment,
nature, etc. When our brains are able to properly receive and organize the data they receive through our ears, we are able
to sense danger, process information and instructions, and feel pleasure through music or sounds of nature. A person whose
senses are well-integrated can sit in the middle of a noisy party with music, talking, glasses and silverware clinking, and
dogs barking, and still be able to carry on a conversation with the person sitting across the table. This person’s brain
simply filters out the unnecessary information, and focuses on the words the individual speaker is saying.
In contrast, a person with SID may hear all of the above sounds at the same level, in effect being bombarded by each of the
sounds. This person will be unlikely to follow the conversation directed at them by the person across the table. Imagine a
similar child in a classroom, surrounded by pencils being sharpened, children talking, music playing, feet shuffling, and
chairs being scraped across the tile floor. This child may not be able to complete the math or reading assignments correctly
with all of the other stimuli overloading his brain. In fact, this child may even exhibit behavioral problems resulting from
his frustration and inability to screen out unnecessary sensory input. The teacher may notice the child "clowning around,"
staring into space, or flapping his hands. This child may become terrified of the fire alarm, perceiving that sound as painful.
Another child may struggle when the room is quiet, because that child is not receiving enough input through his hearing. This
child may begin tapping his pencil, humming, kicking his desk, or otherwise producing his own noise. All children are different
in their needs, but the teacher should be sensitive to the child with SID, taking time to determine whether that child needs a quiet area to study, a set of headphones to block out extra sounds,
or perhaps a stereo headset to provide quiet music. Seeing. Our
eyes provide us with input regarding such things as color, light, movement, locations, body language, and facial expressions.
This information, when properly received and analyzed by our brains, allows us to find our way around,
read, interpret body language and facial expressions, anticipate movement, and sense danger. A child who is under-reactive
to sight stimuli might flick her fingers in front of her face, or hold a book close to her eyes. On the other hand, a child
who is overly-sensitive or overly-reactive to visual input might be frightened in a crowded mall, or become either withdrawn
or hyperactive in a room with bright lights and an abundance of color or movement. People with SID may not respond appropriately
to others’ facial expressions, due to their inability to properly organize visual input. A large classroom which is
visually stimulating, with colored posters, stacks of books, bright lights and windows, rows of desks, and many children,
can be very distracting to the person with SID, and may require that special
accommodations be made for that person.
Smelling. We are often surrounded by fragrant scents from perfume and flowers, and delicious smells of popcorn and freshly-baked
bread or cookies. Other smells we encounter in our environment include cleaning agents, newly mowed grass, car exhaust, and
smoke. Our sense of smell can bring us pleasure, enhance our ability to taste our food, and warn us of danger. However, as
with the other senses, the sense of smell can cause frustration for a person whose brain is not able to properly analyze,
screen out, or respond to the information it receives. Some people are overly sensitive to smells, and a whiff of perfume
or cleansers can be very distressing to them. Other people are under-reactive to smells, and may hold things close to their
nose to be able to smell them better. Whether they are overly- or under-reactive to smells, students who are keenly aware
of the smells around them in the classroom may be unable to concentrate on the work they should be doing.
Taste. Taste often brings us pleasure. We tend to eat the things that taste good! But taste can also warn us of danger. We
know that milk may be sour or food may be spoiled based on the way they taste. But a person with SID may be either a very
picky eater, avoiding certain (or many) tastes and textures, or may be an indiscriminate eater, eating almost anything! Taste
is an area which will likely cause more distress and grief for the parents of children with sensory problems, than for teachers
Touch. We only have two eyes, two ears, and one nose, but our bodies are covered with very sensitive touch receptors. Through
them we get information about hot and cold, hard and soft, smooth and rough, and pain and pleasure. When a person’s
brain is receiving and analyzing this information from the tactile system correctly, he will quickly remove his hand
from a hot stove, put mittens on when going out into the snow, and smile when receiving a caress from a loved one. However,
a person who has SID may react violently to a warm surface or a gentle pat on the back. He may not remember to wear mittens
even on an extremely cold day, or he may always wear long sleeves, even when it’s warm, because he dislikes having his
skin exposed. If he is under-reactive to touch, he may receive a serious wound, acting as though it is merely a scratch. He
may hate to get his hands dirty and to touch unfamiliar objects, or may have an intense need to touch anything and everything.
A child with SID is going to present unique challenges to
the science teacher leading a lab dissecting frogs. This child is either going to resent having to be involved in such a messy
endeavor, or is going to be attacking the frog to find and to handle every slimy bit of the innards. Similar problems may
arise in art class and in the cafeteria. This child may have difficulty standing in line, because either he will be touching
everyone, or he will be complaining that everyone is touching him. Often he may perceive a light touch from a classmate as
a hit, and he may strike out at the other child. Parents may have difficulty choosing a wardrobe for this child, because there
are certain fabrics or articles of clothing that he refuses to wear, or the tags in the back are bothersome to him.
A child with tactile defensiveness or a need to touch things,
may benefit from carrying a stimulating object in his pocket. This may be a small textured ball, a key ring, or something
that vibrates. When the child needs help concentrating, or needs to be able to touch something, he can reach into his pocket
for that item. Many children with SID twirl their hair, rub their fingers together, or even chew their fingernails.
Vestibular System. Although most people are familiar with the above senses, there are actually two other systems that play
a very large role in our brains’ ability to receive information and to respond to it. The first is the vestibular system,
which has to do with movement and balance. A person with SID may be hyper-responsive (over-reactive) to movement,
or hypo-responsive (under-reactive) to movement. Hyper-responsiveness to movement may cause a person to experience motion
sickness in the car or on an amusement park ride. This person may be afraid of heights or dislike being upside down, which
is referred to as gravitational insecurity. This person may seem stiff, and even hold his head upright, to avoid excessive
movement. (Problems with their vestibular system may have caused the strange crawl that both of my sons developed; they did
not like to put their heads down, so crawled in a way that allowed them to keep their heads upright.) A child with these difficulties
may struggle on the playground or in physical education classes, where they may be expected to swing, go on a merry-go-round,
hang upside down, or run.
Hypo-responsiveness to movement may result in a child who
is always moving: spinning, swinging, rocking, flapping her hands, and fidgeting. Many children with SID appear as though
they have Attention Deficit with Hyperactivity Disorder (ADHD) simply because they rarely stop moving. These children often
exhibit poor balance, and may have difficulty navigating around objects, bumping into walls and tripping over chairs. They
might enjoy hanging upside down, and appear able to spin without becoming dizzy. While a child with sensitivity to movement
is going to be presented with many frustrations outdoors, hyperactive children are likely to be more challenged indoors, especially
during times when they are expected to be quiet, focused and attentive.
Proprioceptive System. The last system deals with body position, and is known as the proprioceptive system.
This system is often referred to as "awareness of body in space." When this system functions properly, it allows us to sit
down onto a chair without falling, walk up and down stairs without watching our feet, close a door with just the right amount
of effort, squeeze a glue bottle just hard enough to squirt out a small dot of glue, and walk down a crowded sidewalk without
bumping into anyone. Disturbances in this system can obviously lead to problems. A person who does not know how far her arm
extends may end up hitting someone as she reaches for an object. This person may step on someone’s foot as she walks,
not realizing that a foot was in her way. She may slam doors, or close them so lightly that they do not latch. She may be
clumsy, and may be unable to climb a piece of playground equipment or walk up stairs without difficulty, perhaps needing to
watch her feet to see where to place them. Problems with the proprioceptive system can be the main contributor to difficulties
with motor planning, which is the ability to figure out how to use one’s body. For example, when walking under
a low doorway, most people know just how far to bend down to avoid hitting their head. A person with motor planning difficulties
may bend over too far, or not far enough. This person may not know how to climb up the monkey bars on the playground, or may
not be able to get down once she is up there! Routine tasks such as dressing, tying shoes, eating with utensils, and writing
can be challenges for people with motor planning difficulties.